Oops. Sorry, Insanistis. (I saw your post after I posted my post, which is unusual.) Both of the Rowton books do look very good. In addition, I checked out Dan Heisman's chess recommendations, and they look great also. I will look at Chernev's other book. Does anyone know of any annotated game collections in addition to those books? I am hoping to play through a bunch of them this summer.
What was the best chess purchase that you ever made?

Should I spend my money on the membership or on the books? Which would be more useful in the long run?

Probably a chess instructor if you can afford one. A good instructor will be able to point to areas of specific weakness that need work.

Ok, living in Seattle, there are plenty of options. Would anyone recommend a chess coach either here on chess.com or on other online places?

My best chess purchase, as mentioned by others, is membership in this site. Chess mentor is good and the videos are great. You would have to spend a lot of money just for videos alone.

So the gold membership would be good. I also have a chesstempo.com account, so that is good for tactics.
My favorite chess book that I ever read (library,not bought) : Chess for Dummies. I think it works for any level.

No, absolutely not, chess mentor is just a glorified tactics trainer. It doesnt mentor you.
Amazingly wrong. Yes there are tactics courses available on CM, but courses also on strategy, openings, the psychology of chess, Silman's imbalances, and pretty much anything else you can think of. The better courses do mentor you by giving detailed explanations of not only why the correct answer, but also why not your answer. There are some incredibly well done courses on CM. It is about the furthest thing possible from a "glorified tactics trainer".

Ok, so I think it would be good to go over plenty of annotated games and endgames, and possibly try the memberships. Are there any books like Chernev's "Logical Chess Move by Move" that are good?
http://www.chess.com/blog/NimzoRoy/beginner-chess-book-recommendations

Best chess purchase - my Diamond membership to this site.
Second best chess purchase - when I won an ebay bid a couple of years ago for a HOS Reykjavic bloodwood and ebony chess set.
Chernev - The Most Instructive Games of Chess Ever Played
Giddins - 50 Essential Chess Lessons
Neil McDonald - Chess: The Art of Logical Thinking