Most Realestate agents will be looking in their best interest which is to sell you something with as little work as possible. Make sure you are as informed as you can be about buying a place It's just like advice they give for an interview, you don't want your first one to be the job/or house you really want. Look at as many units as you can to get a better understanding of the market. At least where I am at you don't have much time to snatch up the good ones. You need to be able to evaluate them in as quick a time as possible. It also helps you to familarize yourself with different types of heating, plumbing, electrical and structural differences. A good experienced agent should point these things out and help with the pro's and cons of each.
I bought two, one within 3 hours of it posting, the second one they didn't allow viewings, so I asked the tenants as they were moving out if I could check it out. I knew from looking around the area that both places were a steal the second I stepped into them.

you can buy mine. i hate landlording!

There are some signs of gentrification or rejuvenation of a neighborhood, such as infrustructure projects, new chain stores moving in to a neighborhood, such as Whole Foods, Starbucks.

I'd get several agents working for you - or at least tell them the types of property you'd be interested in buying so if they come across one - then they'll give you a call.

I'd also check Realtor.com and other sites for listings. But, word of mouth from agents is the best.

What I have found that works is two different things:

1) Get to know a bunch of real estaet agents and let them know you're looking for a place. They will be a great source of leads

2) Drive around and look at buildings you like. Research who the owner is and approach them.

Not sure if there are any online resources other than the typical real estate listing sites.
Good luck!