A few years back I used to play with a player who always accepted the queens gambit pawn and used to hold on to it and sometimes win with the pawn plus. Is there any specific variation that can be studied in favour of black in queen's gambit accepted?
Black can sometimes hold on to the Pawn if that is the goal. Black has to play an early a6 and b5. One possible variation is:
[FEN ""] 1. d4 d5 2. c4 dxc4 3. Nf3 a6 4. e3 b5
Although Black will hold on to the extra C-Pawn, White can counterattack with
Nc3. Black has neglected development, and according to MegaBase 2012, White scores 60.6% from the diagrammed position with the move
There are ways to hold onto the pawn, but most of them leave Black with a dreadful position where his entire position is built around hanging onto the pawn. Moves like
Qa5 are examples of strategies that could be employed.
In the Slav and Semi-Slav defenses, there are in fact a lot of variations in which black is able to comfortably (somewhat) hold onto the pawn. I would check those out if I were you.