I'm currently trying to assemble some sound design contacts that specialize in production music and creating loops for some mobile and web apps. Similar to say, what is available on beatport. However, I'm finding this task quite difficult - anyone have any recommendations?
Perhaps check out some forum sites for game programmers. Often there is a thread devoted to people such as musicians hoping to make contact with game programmers. I am thinking, in specific, of Java-gaming.org where there is a Jobs and Resumes thread.
I know there are composers that have advertised themselves there. Even if you have nothing to do with Java, the composers that have posted links to their sample pages probably can provide cues and music for a game written in any language.
Surely there are other game-programming forums out there like this with similar threads, as well.
I also have met composers at Game-Development Meetup groups, like San Francisco Game Developers. You don't even have to sign up for local Meetups, but can often communicate with members via joining and messaging.
There are meetups that are even more focused on game music out there, I'm sure, and they shouldn't be hard to find.
As stated games design websites with an audio section could work, however you might be very stylised "gamey" sounding loops.
If you're after production quality, then I would scour soundcloud and ask smaller artists (in the niche you are after), if they would be able to help, directly ask at the source.
I have a bias answer that is myself: https://soundcloud.com/mouldysoul
I've been producing for around 12 years now, had a string of releases of beatport including remixes, few ep's and an album "Senses".
I have a rather large extended network of sound designers and producers I could also recommend that I know from festivals and gigs, if you'd like to PM me.