I just recently bought my first house so cash is kind of tight but I want to add sources of cash flow more than ever now that I have a mortgage.

Paying down a mortgage does not increase cash flow it simply shifts the income source from the property to the equity.

However, since private lending is  likely THE source of real estate investing financing for the short- and mid-term future, it would be well worth the effort, I'm thinking.

A great online source that we use is www.loopnet.com.

I'd love to source your next deal.

Now that source of income is a protected status in CO, landlords can't deny a tenant based on the applicant using a voucher so govt. subsidized renters can rent anywhere that they can find something they can afford.

After a few of those I felt comfortable enough to start investing in deals I sourced and managed. 

.$20k-$50k is a good amount to fund 2-3x improvements for people looking to sell with clear improvement scopes of work with trustworthy contractors on 2nds up to 60% LTV.These are harder to find, especially with fewer people selling, but I suppose a network of agents,  title cos and lenders would help source opportunities in this space. 

I want to explore Section 8 as a RE strategyKeep in mind that subsidized tenants can use their voucher in any neighborhood (especially in states like MD where "source of income" is a protected class).

Lenders, agents, wholesalers, brokers, contractors, distressed sellers, capital sources, gurus, internet forums on real estate, other investors.