I've visited Bangkok a number of times in recent years, and it remains one of the most reasonably priced, tourist-friendly cities in the world. My personal favorite is the small Swiss Lodge hotel, which draws many business travelers. It's adjacent to a Catholic girls school in central Bangkok. Then there's the Narai Hotel, which is large and popular with tourists. I've stayed at both places. I've used hotel search engine agoda.com to book Thailand hotels. Its reviews and ratings are very helpful.