carl1864, there is definitely a big difference between certification classes, and I would VERY highly recommend not using price as a determining factor for deciding where to get certified, particularly if you are a little ambivalent about local diving. Cheap classes give you very little pool time to become accustomed to your equipment and get comfortable in the water, and often run large groups of students through their OW dives, which results in very poor visibility and signfiicantly increased diver stress.
I would look for a shop that offers a lot of pool time (Bubbles Below in Woodinville, for example, has six pool sessions of 1 1/2 hours apiece). I'd also look for a shop that makes a point of low student to staff ratios. Open water dives in the training sites in the Sound WILL be low viz dives, because new divers really can't help disturbing the bottom sediments, and it's important to have a lot of supervisory folks in the water. Puget Sound is also cold, so sitting on the bottom awaiting your turn to do skills is not fun.
My personal recommendations are going to be a little skewed, but I'd highly recommend Brian Wiederspan of frogkickdiving.com as an open water instructor. Scott Lundy, who teaches through Northwest Sports Divers, would be another good choice. And my husband, Peter Guy here on SB, is an independent instructor who brings experience in cave and technical diving to his teaching, and also offers the ability to be very flexible on schedule (see, I told you it would be skewed!) Of course, some things depend on where you are near Seattle -- if you are in the south end, I can talk to some friends and get recommendations for down there.
I'm not sure what rental costs are, but I believe Bubbles rents a regulator and BC for about $30 a day (not sure if that includes wetsuit, but you would want to buy that, because proper fit is critical for a wetsuit to work to keep you warm. Luckily, wet suits aren't horribly expensive.)
If you are interested in talking about educational options here, or just about diving, please feel free to PM me, and I'll send you my phone number.