Look for Text-Only/Chat-Only games, play by Post (PbP), or if your restrictions are strictly just Skype (is Google Handouts or Ventrillo an option or is all voice chat entirely out?). Alternatively (and I recommend this for everyone) Create your own detailed forum post to state what you're looking for, your gaming experience, date/time availability, time zone, etc... everything any GM needs to know about you to determine if you're a good fit to their game. Finding a quality game on Roll20 is just as arduous as finding a sit-down group. Try not to get discouraged if it takes a couple weeks to find something that suits your needs.