There are regular buses in both directions of Highway 13, i.e. to Vientiane and Pakse (US$10, 10h to 15h depending on the bus) and everywhere in between. Buses going to Vietnam by the Cau Treo border also pass here. The most popular boarding place is in front of the market (on the other side of the bridge than the Paksan Hotel). Just flag anything down you like.
For buses to more local destinations, there's a bus terminal next to the market.
Noodle soup and sometimes also a bit more variety in dishes can be found at and opposite the market and also on the east side of the bridge.
There are a few guesthouses around town, particularly at the eastern and western ends of the town along Highway 13. The following options are within a reasonable distance of the market and the main bus terminal.