Taz records
1593 Market Street, Halifax
By far the largest store in the area, it has a quite extensive selection, bought some interesting stuff her, for example Dieter Moebius - Tonspuren, UR - the final frontier. The dollar bins were intesting too for example picked I F playstation 2 promo, Martin Circus - Disco Circus, John Foxx - John Foxx form here.

Obsolete Records
2454 Agricola St, Halifax
I didn't think this shop was too interesting. It's a small shop and mostly sells new indie/punk stuff. Not necessarily bad, but it was not really what I was after. Bought one 2nd hand punk/hardcore 6" though.

Select Sounds
1475 Bedford Hwy, Bedford, located in a little mall.
This shop is located in Bedford which is not far from Halifax, you can get there either by car, or take bus 80 to Sackville.
I found this store pretty interesting and worth taking the bus to this place
The shops sells vinyl (and cd's) ranging from 60's stuff, to classical, alternative/metal, some new stuff and all things inbetween. I bought UR- Interstellar Fugitives 3lp, Trisomie 21 chapter IV, and some other stuff there.

CD heaven
118 Wyse Rd, Dartmouth right across MacDonald bridge.
This shop is located in the Dartmouth shopping centre and like the name suggests it sells mostly cd's. However they had a small vinyl section. Not too interesting in my opinion, I only bought Paul McCartney II (with Temporary Secretary on it) here.

Thrift Stores:
Besides these store there are several thrift stores that have a  few records too, there quite some Salvation Army Thrift stores here. The records they sell are mostly junk, but you never know what you will find on forehand. Didn't buy a really interesting record there. I decided to buy some cassettes for 49cents. Best find was an Iron Maiden - Maiden Japan cassette.
I found the thrift stores( as well as the record stores) using yelp by the way: http://www.yelp.ca/halifax

Flea markets:
2901 Windsor St, Halifax
There's a flea market in the Halifax Forum on sundays, from 9:00 til 14:00 admission is 1,5$
http://www.fleamarketsandauctions.com/
There was one guy that only sold vinyl, and some people that had a few record. I bought George Harrison's - Electronic Sound here and a few other things. I also bought some cheap bollywood 7"s, but I haven't heard them yet.

There's also some sort of fleamarket in Dartmouth on saturday and sunday, but I haven't visited it yet. It's called the Harbourview Weekend Market and i'm planning to go there this weekend.