Recommendation of a good editor?

I once pondered the same question and set out on a journey to find one. Unfortunately, all I found were poorly crafted websites, websites that hadn't been updated in years, and "editors" hiding on obscure sections of the internet with little to no credible references.

I'm certain there's legitimate editors out there, but I haven't yet found one I'd trust with my money or manuscript.

Define affordable?

It sounds like you need more than just copy-editing. A full manuscript edit from a reputable, experience editor will run you anywhere from 400 to 1500 bucks, easily.

I use Lynn O'Dell at RedAdept Reviews. Not inexpensive, but worth it, especially if you spring for the additional proofreads done by other folks on staff.

Or you could save yourself some money, set your book aside for a while and read...read a lot. Also, post a piece on the relevant SYW forum (when you've reached 50 posts). Haunt the SYW forums, read what other people have posted and what critters have said about those pieces.
Don't rush into anything, don't shell out for an expensive qualified editor, if you can learn to fix things for yourself.

First step: Learn grammar. I'm sure that there's a Freshman Comp class at a local community college that'll cost you a heck of a lot less than the $1500/book that a real editor will charge.

Pick up:

Self-editing for Fiction Writers
The First Five Pages
The Transitive Vampire
Eats, Shoots & Leaves
The Elements of Style
Any high-school English review workbook

Plus read a lot, write a lot, correct yourself, get beta readers, join a writing group, etc.

Writing isn't something that you fix by waving a credit card at it.