Have a look in the mining pools thread.
https://bitcointalk.org/index.php?board=41.0

Specifically
This one which is slush's stratum server
https://bitcointalk.org/index.php?topic=108533.0

which generalfault expanded on a bit and the git respository for it is here

https://github.com/generalfault/stratum-mining

Managed to get this basically working in the last couple of days.

There is also eloipool
https://bitcointalk.org/index.php?topic=61731.0

setting up for solo

https://bitcointalk.org/index.php?topic=158105.0

I managed to get the server started, but not with midstate as I cant get it to compile.
Havent gotten around to testing the server yet.

There is a list at

https://en.bitcoin.it/wiki/Software#Mining_Pool_Servers_.28backend.29

only one current on there is eloipool.

Edit: To add there is really no easy setup and go, out there without paying someone to write it unless you can do it yourself.