I am a web designer primarily, but I could probably help you out. Email me at inlith@gmail.com
My portfolio is at madebyargon.com, but again it only showcases my website and UI design work.
Charging you $600 for a 4-5 hour work, its just symbolic. The amount of work put on a logo easily takes a couple days if not weeks to come up with the final design.
For instance, Comedy Central was charged $1MM for their logo redesign and the agency charged them for just "1 hour" of work. This doesnt mean they normally charge $1MM per hour.
Designing a logo is one of those things, like naming, where lots of effort may be spent on seemingly small outcomes. That's because a good designer will generate a ton of options and spend a long time thinking about what message your logo needs to convey.
You usually get pretty reasonable bids on there, plus you can check out individuals portfolio and see if they have done anything similar before.