Newbie building modest system ...what amp?

I have a adcom gtp 400, rega rp1 so far with kimber kables for interconnects and speaker cables.

In search of Vandersteen 2ce's.

Looking to spend in the 500-600 range used for a power amp. Then will be on the hunt for a used preamp after that.

Any input would be appreciated.
Sell the GTP-400, add it to your other money and buy a decent integrated amp. The Adcom pre is a POS, I know as I owned one.
Any old Rega, Arcam, or Linn, will do just fine. Dump the adcom as soon ad you can, you won't believe the difference.
I've owned 2ce's, 2ce Signatures and 3a Signatures. I'd look for a McCormack DNA .5 Absolutely perfect match for Vandersteens. You may be able to find a DNA 1.0 in your price range and it does have more power, but I've always found the DNA .5 to be slightly smoother in the treble.