The Spyderco Sharpmaker is an easy way to get a nice edge. It is pricey at $56, but it should last you for years and years, and you can sharpen damn near anything with it, including scissors, chisels, awls, fishhooks, etc.

Also, /r/knives would be a better place to get answers to this question.

I've only sent one knife in to the mothership to be sharpened and it turned out great. The only reason I sent it in was I had a hard time getting the tip sharp. That being said, invest in a good sharpening system and a strop. It's a skill worth having and will save you a lot of time.

For touch ups I've had great results with the Spyderco Sharpmaker. Also the Work Sharp Field Sharpener and even the Lansky Turn box or Lansky Masters Edge.

The Work Sharp Precision is good too but better for reprofiling IMHO.

And I have a strop from Stropman.