The Google map location is given here.
Tbilisi Public Transport Usage Guide
If you take taxi from the airport it will cost you 35 LARI which you should exchange money at the airport (withdraw money from a cash machine at the airport). Don't let taxi driver to cheat you - the rate is 35 LARI to our hostel.
Another way is to take a bus #37 which costs 50 TETRI per person which you also should have. The bus is round-the-clock: 7:00 a.m. - 12:00 p.m. it runs every 20 minutes and from 12:00 p.m. till 7:00 a.m. the interval is 35 minutes. You can exchange some money (including coins) also at the airport at the bank office.
Georgian Lari is a currency of Georgia. ISO code is GEL. Georgian Lari is subdivided into 100 Tetri.
If you pay cash in a bus you should have change - 5, 10, 20 or 50 tetri coins. You can use 1 lari coin to purchase 2 tickets and 2 lari coin to purchase 4 tickets. If you pay in mini-bus - you pay to a driver. But this does not play in metro. You can't pay cash in metro - you must have plastic card. In general it would be advisable to buy a plastic card which is good for buses, metro and mini-buses ("marshrutka"). You can purchase the card in any metro station. It costs 2 lari (keep payment check if you are going to return the card within one month and get your money back) and you should credit it (in metro or with the use of payment terminals which are set on any bus stop and in the streets) when necessary. You can return your plastic card (in metro cash office) within a month after purchase upon submission of payment check and your ID card and get your 2 lari back. One metro or bus trip at any distance costs 50 tetri. Payment fee for additional use of the same plastic card within 1.5 hours is 0. After 1.5 hours you pay again 50 tetri and enjoy 1.5 hours more free of charge traveling. One trip in "marshrutka" is 0.8 lari (80 tetri) and any next trip within one day will cost you 65 tetri if you pay with plastic card. But the use of plastic card in a bus or metro does not provide the right of discount for mini-bus and vise-versa.
If you are a group of tourists it makes sense to purchase one plastic card and use it to buy relevant number of tickets (no discounts and free 1.5 hour are applicable for the whole group in this case).
Don't attempt to travel without a ticket - the authorized inspectors are very strict and they are monitoring all the buses day and night. The fine is 5 lari and if not paid at a bank or payment terminal in the street within a month the fine increases up to 50 lari.