Heres a basic pump for those interested.
2" PVC Pipe
1" PVC Pipe
2" Cap
1" Cap
1" T
2" Test Plug
I didnt measure when I did mine, you can use your own judgement. Theres plenty of "how to videos" on you tube but here the basic pump. Its worked great for me, caught plenty of ghost shrimp last year. Also Im sure you can grab one @ J&M's.
http://i53.tinypic.com/2vs5l79.jpg
http://i55.tinypic.com/5dqtd0.jpg
http://i56.tinypic.com/5ow47n.jpg
http://i56.tinypic.com/120l8j5.jpg
I found the best time to go is at low tide, look for the holes and start pumping. During the Winter I found them to be closer to the surface but the few times I looked for them during the summer they were much deeper.
Hope this helps yall.