Can you not have the formatting and the covers done at the same time? Like others, I can't really imagine why it would matter which one you do first.
Or just hire out the covers and do the formatting yourself in the meantime. It's really not that difficult. I couldn't imagine paying someone to do it for me.
And yes, if you have no design/art experience (or software), definitely hire the covers out. You can probably dig up a designer here, and there are some designers that offer unique pre-made covers (that they'll add your name and title to) for very reasonable prices.