Get in Lebanon
Entry will be refused to citizens of Israel and travellers with any evidence of visiting Israel: not just Israeli entry stamps, but Egyptian / Jordanian neighbouring land borders with Israel, any products with Hebrew labelling, etc.
Citizens of Iran and Turkey get a free 3 month visa that can only be renewed before one month passes since their entry.
Citizens of: Egypt – Sudan – Tunisia – Morocco – Algeria – Libya – Yemen – Somalia – Djibouti – Mauritania – Comers Island – Nigeria, Ghana, Ivory Coast get a free one month tourist visa provided they have a two way travel ticket, a hotel reservation/place of residence and US$2,000 (The cash conditions can be exempted if you get the visa from the Lebanese embassy beforehand).
Citizens of Thailand (and several other countries not otherwise listed in this section) cannot get a visa directly at the airport or at a Lebanese embassy. Instead, a visa needs to be arranged by a Lebanese sponsor in Lebanon through the General Security head office in Beirut. This is a convoluted process that can take months, so start early. Visas issued this way are valid for 1 month but can be extended till 3 months at Sureté Générale once in Lebanon.
Three-month visas are free for nationals from Gulf Cooperation Council (GCC) countries and Jordan. Other nationals can obtain a 15-day visa for LL25,000 (US$17), or a three-month visa for LL50,000 (US$35). These visas are single-entry; nationals of many countries can also obtain multiple-entry visas ($75 valid for six months). The 48 hour free of charge transit visas (valid for three calendar days) are still issued, but only if you enter by land and leave via the airport or vice-versa.
Visas can be obtained at Lebanese embassies and consulates in other countries, or upon arrival at Beirut airport and other points of entry for some nationalities.
A free one month valid visa, automatically renewed once (therefore, for a maximum stay of 2 months), is granted to the citizens of these countries who are coming for tourism: Andorra, Antigua and Barbuda, Argentina, Armenia, Australia, Austria, Azerbaijan, Bahamas, Barbados,Belarus, Belgium, Belize, Bhutan, Brazil, Bulgaria, Canada, Chile, Czech Republic, Costa Rica, Croatia, Cyprus, Denmark, Estonia, Finland, France, Georgia, Germany, Greece, Hong Kong, Hungary, Iceland, Ireland, Italy, Japan, Kazakhstan, Kyrgyzstan, Latvia, Lithuania, Liechtenstein, Luxembourg, Macedonia, Macau, Malaysia, Malta, Mexico, Moldova, Monaco, Netherlands, New Zealand, Norway, Palau, Panama, Peru, Poland, Portugal, Russia, Romania, Saint Kitts and Nevis, Samoa, San Marino, Singapore, Slovakia, Slovenia, South Korea, Spain, Sweden, Switzerland, Tajikistan, Turkey, Trinidad and Tobago, Turkmenistan, United Kingdom, USA, Ukraine, Uzbekistan and Venezuela. The easiest way to renew this tourist visa after these 2 months is to leave the country and come back the day after. Due to the Syrian question, the only way to currently do this is to fly to Cyprus or Turkey which are the cheapest destinations.
After these 2 months, if you don’t leave the country (or get a work permit), you will have to regularise your situation with Sureté Générale’s offices in Beirut. (This is a special building – don’t go to the main office on Damas St – ask the guards for the precise address.) There, to be allowed to leave the country, you’ll have to pay a 50,000 LBP (30$) fee, which will grant you 7 days to leave the country. [Information dated of May 2012]
Beirut International Airport (BEY), is located 5 km (3 mi) south of the city centre) – Middle East Airlines  services daily to Abidjan, Abu Dhabi, Accra, Amman, Athens, Cairo, Cologne, Copenhagen, Dammam, Doha, Dubai, Frankfurt, Geneva, Istanbul-Ataturk, Jeddah, Kano, Kuwait, Lagos, Larnaca, London-Heathrow, Milan-Malpensa, Nice, Paris-Charles de Gaulle, Riyadh and Rome-Fiumicino, Warsaw-Okęcie.
In addition the Airport is served by foreign airlines
Middle East (Arabic countries)
Air Algérie (Algiers)
Air Arabia  (Sharjah, United Arab Emirates, Alexandria-Borg Al Arab)
EgyptAir (Cairo, Alexandria-El Nohza)
Emirates Airline (Dubai)
Etihad Airways (Abu Dhabi)
FlyDubai  (Dubai)
Gulf Air (Bahrain)
Iran Air (Tehran-Imam Khomeini)
Jazeera Airways (Dubai, Kuwait)
Kuwait Airways (Kuwait)
Oman Air (Dubai, Muscat)
Qatar Airways  (Doha)
RAK Airways (Ras Al Khaimah)
Royal Air Maroc (Casablanca)
Royal Jordanian (Amman)
Saudi Arabian Airlines (Jeddah, Riyadh)
Wataniya Airways (Kuwait) (Not currently in operation)
Yemenia (Amman, Sanaa)
Air France  (Paris-Charles de Gaulle, Marseille)
BMI  (Khartoum, London-Heathrow)
Bulgaria Air (Sofia)
Cyprus Airways  (Larnaca)
Czech Airlines  (Prague)
LOT Polish Airlines 
Malév Hungarian Airlines (Budapest)
Olympic Airlines (Athens)
Turkish Airlines  (Istanbul-Ataturk)
Viking Airlines (Stockholm-Arlanda)
Malaysia Airlines (Dubai, Kuala Lumpur)
Ethiopian Airlines (Addis Ababa)
For flights from the United Kingdom try Turkish Airlines , Cyprus Airways  or Czech Airlines . These three airlines are often cheaper even than MEA or BMI direct from Heathrow. Czech airlines are consistently the cheapest bet from Manchester.
Direct flights from the U.S were again permitted by the U.S Government effective June 9, 2007; however, at present no airline offers direct service to the Americas from Beirut.
As of February 2013, Lebanon essentially became a fly-in, fly-out territory for tourists, with the ongoing civil war enveloping Syria and ferries from Turkey and Cyprus showing no sign of resumption.
In the peaceful times, buses would leave Damascus every hour and typically cost 400 or 500 SYP. The trip is normally 4-5 hours, depending on traffic at the border. Note that when leaving Syria, you must pay an exit fee of 550 SYP and must acquire a Lebanese visa on the other side of the border (48 hrs Transit Visa is free, 15 day Transit Visa is LL25,000 (US$17), single-entry 30 day Tourist Visa is LL50,000 (US$34), payable in Lebanese Pounds only. Money changers can exchange currency, typically with a $1 exchange fee).
There are no such services available, but there are many companies that offer visits to Lebanon on a cruise.