If you can PRP I would continue to do so as long as your patience holds out. The sieving effort is important, but the primary goal of this project is to find 12 more primes! The sieving effort helps by eliminating candidates from the PRP process. As long as it eliminates them more efficiently than PRPing, or at least as efficiently, it will and should be pursued.
Having said that, if you are still interested in sieving, I will try to gather the information here for you. Check back to this post, as I will edit it instead of posting again when I get more info gathered.
There are currently two sieving efforts. The first is 3M < N < 20M, and the second is 101 < N < 3M. They use the same programs but different SOB.DAT files.
The programs and the 3M < N < 20M SOB.DAT can be found on this page, with an updated program in this thread. The coordination thread for this primary sieving effort can be found here, in this thread. This is where most of the sieving effort is concentrated.
In the unlikely event that we will have to go back and double check our efforts, there is a second sieving effort preparing the way. The SOB.DAT file for this 101 < N < 3M double checking effort can be found in this coordination thread, with a discussion in this thread.