Pak Beng Village is a quiet small country town with quite a few of guesthouses, riverside restaurants (15,000+ kip for a main dish; 10,000 kip for a large beer), bakeries (10,000-20,000 kip), and shops (5000 kip for a 1.5 L bottled water). There are also 2 ATM's (turn right up the hill, straight down the road). At the pier, people with signs might try to sell accommodation, but it's probably better for you to see the place for yourself first before deciding. The town is pretty small so it's totally walkable.
We walked around town and asked a few decent-looking places for their prices — prices range from 200 baht to $50 USD per room. If you turn right after going up the hill form the pier, there are many guesthouses for around 300 baht a night. Almost all the guesthouses are less than a 5-minute walk from the pier, up the hill.
We had dinner at a family-run riverside restaurant, and the little girl who cleared our table just cleaned our plates by brushing everything left over off the balcony, down the river bank. If you're lucky, you might see some elephants feeding at the riverbank early morning.
The stores are open pretty early in the morning so you can get some bakery goods or sandwiches for the slow boat to Luang Prabang. It's lovely to walk around in the morning, as it's all misty, quiet, and beautiful.