If you're in the Bay Area, Wharton West and Haas would seem to be the logical first choices. I'm a current WEMBA student (East) and it's billed as rigorous as the FT program (same courses, instructors, load). After 3 weeks... check, check and double check. I don't know how others manage the travel logistics (we have someone flying in from Belgium), but convenience was important to me. I considered Kellogg and BSB as possible alternatives if I didn't get into Wharton, but the idea of flying into Chicago twice a month on a tight schedule was onerous. After consideration, Columbia became my actual fallback. Long story shorter: I'm a big fan of focusing locally if you can. You're probably going to be so busy the additional travel overhead will be another force pulling at your job, homelife and school.
If you really want to travel, Columbia, Cornell and NYU are respected NYC options. UCLA and USC to the south would also bear consideration. Chicago BSB. You might want to track down maybe the Business Week or FT EMBA rankings as a starting point to identify the usual suspects, as I'm certainly omitting a few.
The application process varies by school, obviously. Invest the effort and get the GMAT score you need to get in. Our class' median score was just over 700 iirc. Over 700 won't guarantee you much, however--there were decent interviewees on my day that didn't get in with 720. For my money, you've found this forum, that's probably half the battle. Spend the time and effort, get a good GMAT if you want to attend one of the better EMBA programs--it might be as much as 90% effort and only 10% ability if you ask me.
I didn't do receptions or networking, but I have more career experience than most of my classmates. My GMATs were good, my essays were probably a B (one good, two of them... ehhhhhhh...). No idea about my interview--it was a pleasant conversation but it was unstructured and I should have pushed the agenda a bit more to make my case for admission. In retrospect, I spent a lot of time and effort. I'm thankful it worked out.
Which leads me to my only real advice: have a backup plan. I only applied to Wharton. If that had failed, I would have had to pick up the pieces and regroup. I might have quit on the idea, as I wasn't truly excited about Columbia. Having been through the process, my conclusion is that it's fairly fickle. I think adcom does the best they can, but it's a difficult process--they really just have a keyhole view of their applicants. They make the best calls they can and benefit from having a good pool to choose from. I know I could have just as easily been one of the non-admits though. Have a backup plan.
Read back through and look for RVDs posts and go to whartonblog.com and execmbajourney.blogspot.com. Read about what doing this is really like. The various WEMBA blogs were a great source of information (and inspiration) for me (thx to RVD and Chairman P), I think I read every post. I recommend really trying to understand what the program is like--the official brochures and web site are going to tell you this is a lot of work and a big commitment, but I think it helps to get a picture of what that really means in real world terms.
Good luck. It's a good time to start the process imo--I think I started getting down to business about May of last year.