Before booking your hotel you might care to Google for Precision Reservations Thailand. A selection of hotels in the location of choice will be shown. If you book at least 3 days before arrival you will pay about 60% of rack room rate. Walking in off the street will cost you money. Then check the asking price against what the hotel want.
I have lived in Thailand for 5 years and travel around quite a bit. I always use this service and has saved me a bomb. Regular users get bonuses.
When I first arrived at about 7 in the morning I got a "airport mafia" taxi into Krung Thep costing 300 baht. I'm not a skinflint but hate being taken for a ride - if you'll excuse the expression. :-) Now I walk out of the airport to the main road and flag a taxi down. Ensure that the meter works - if not tell the driver to go forth and multiply. Trip to town should be about 70 baht. I always pay twice the meter fare as the authorised fares are far too low.
After 11 hours at the tender mercies of Thai Air, or some other airborne bus company, you'll be shagged out and a night in a Bangkok hotel (pre-booked!) will be welcome. Will give you the chance to shower, kip and have a walk round the fleshpots of Sukhumvit Road. That you are a tourist will be picked up on immediately ( clothes, pasty white skin, bewildered look on face) and you'll be excessively charged for everything. In the morning catch the Skytrain to Ekamai bus station for a bus toPattaya. Fare now 105 baht I think, versus 1500 baht by taxi. You may strike lucky and meet a returning TBG on the bus. At Pattaya bus station on Pattaya Nua you will be confronted with the notorious baht bus mafia. These hoods seem to have the Mayor and police in their pockets. DO NOT MESS WITH THEM. If you have light luggage i.e. you have followed advice and taken the minimum of everything, a taxi motor bike will take you to where you want to go and 70 baht should get you anywhere in town. You may find yourself offering Hail Marys in an upward direction until you get used to the kamikaze riders.
No No's to first time visitors. Do not get into heated arguments with Thais. NEVER hit a Thai unless you want a severe beating from a mob. Thais stick together, and for many, behind the ingratiating smiles is a deep contempt for Farangs. Avoid all contact with the police - even the Thais hate them. It is reckoned that half the crime in Thailand is carried out by them. Never carry around more money than you can afford to lose. If a gorgeous young thing comes up to you and throws her arms around you, hang on to your wallet, gold chain, watch etc. You're being frisked and dipped by a fella (of sorts) and they are experts. If you want something done,get a woman to do it for you; most Thai men that you will come into contact with are totally moronic.
I am not the oracle but that is my take on things - for what it is worth. Have fun - but be careful.
P.S. The FLB bar on Walking Street is OK. Their parties are wild. IMHO the best ST bar in town is TJ's (Terry's) on Soi 6, the best English pub and restaurant is The Pig and Whistle, on Soi 7.