Depends if you are looking for a basic refurb ( blasted and repainted ) or a specialist finish (diamond cut , mirror polish etc )
If it is a basic refurb, then more or less one place is as good as the next TBH... the finish will last a while ( probably until the wheels are kerbed) and then you can have them re-done, the price will reflect this.....
If you are after a 'show' finish, then David has recommended two places .... once again, the price will reflect this......
KLP has a good wheel refurber , but he is in Herts, but i gather he is very very good....
Some of the more specialist places will collect (but will charge you for it)
Good luck