Do pcb manufacturers solder components as well?
Some board houses also do assembly. If it's not on their website, simply ask them. They will tell you what they need, and give you any instructions for components you need to supply. A lot of times they will run some kind of special, where you get some deal on assembly for buying boards from them. That said, there are usually NRE costs associated with assembly and it really doesn't make sense to do this for just a few boards.