Our loan was sold off to Wells Fargo shortly after we purchased our home (4.75% fixed 30 yr term, 20% down). Three years in, rates were so low that I decided to look to refi. I shopped around 5-6 firms, including Wells, and they didn't make the cut because they offered a 4.25% fixed 30 yr with ~$8K in closing costs. I ended up getting a 3.25 fixed 30 yr with NO CLOSING COSTS (and no discount points, etc.). I paid for title insurance (discounted since I used the same title company) and the appraisal. 3 months after the refi, Wells Fargo bought our loan again!

Your mortgage company should lead you through the process. Note that many of the fees are negotiable and although the mortgage company may recommend service providers (i.e., title company) many times you have options there as well.