All comes down to sourcing good deals and putting together a solid team.

I am looking for sources that have very up-to-date current pre-foreclosure information. 

a friend of mine and i are meeting in a few hours to start planning for our first property purchase. we both live in manhattan and are looking to purchase a 4-6 unit residential building in the nyc metro area (most likely an outer borough or nj) to begin buying and holding properties. we are looking for properties that will require work / reparis upfront. what are some important first steps that you would discuss with a partner upon starting up (i.e. financing, partnership structures, deal sourcing, property management, business incorporation, etc etc etc.). my background is in finance, and his is in architecture, and we're friends from college.

I like my career but don't want to rely on it as my sole source of income.

For you that is likely whatever job you work at that gave you this additional capital to invest.If you are someone who is looking to create a primary or even secondary source of income or wealth through active real estate investing then yes you should absolutely get your real estate license.

The more sources you contact, the more likely you will be to find the right partner.

In the past I have done my own taxes, but in 2016 I sold my deceased mother's home and purchased a rental property at the end of the year (no income source for 2016, just expenditures).  

A good online source for the above is rentfaxpro. 

In my opinion, it's the best source of money when starting out.  

@Aaron Bruenger is a great source and someone you should reach out to.