Enter the 15 freqs from the east site in one bank, and the other 15 freqs from the west site in another bank. The Hillsborough system is found in the database here:
http://www.radioreference.com/apps/db/?sid=220
Make sure you enter your freqs starting on your scanner's channel 1 for whatever bank you're using (the last freq should be in the channel 15 slot). Each freq corresponds with a "logical channel number" or "LCN" used by the EDACS system. If the freqs aren't in the right channel slots, the scanner will not follow conversations correctly. Also remember to set your bank to EDACS if you haven't already. If it's not set to EDACS, the scanner will stop on the control channel (the freq that sounds like a motorboat). Whatever you do, don't lock out the control channel (it will change frequently) - the scanner needs it to follow conversations properly.
Then add District 2 & 4, Special Events, and all other SO talkgroups to the "east" bank. Then add District 1 & 3, Disaster Team, USF PD and all other SO talkgroups to your "west" bank. As far as the digital talkgroups, you may add them, but do not expect to hear any traffic (any of the District 1-4 Tac D, Supervisors talkgroups). However, you will hear occasional one-sided traffic on the aviation digital and some of the ERT, URT, BDT, etc. talkgroups, but only because the dispatch console is using analog voice - and sometimes that's enough to figure out what's going on. There is no scanner on the market that will monitor EDACS digital voice (ProVoice, AEGIS, or whatever it might be).
Also, I read on another group where someone told you that FR is simulcasted on both sites. That is only partially correct. Only the dispatch talkgroup is simulcasted. FR is divided into east and west like the SO, with east side units using the odd numbered Tac channels, and the west side using the even numbered Tac channels. Units will respond on Tac 1 (east) or Tac 2 (west), and use the higher corresponding odd or even channels as fireground/working channels.
Not sure where you're located, but you may need an 800MHz band antenna to pull in the west site. I'm in Brandon, and when I'm downstairs I have to use my Radioware Seeker antenna to hear the west site. My Radio Shack antenna will hear the west site fine when I'm upstairs. If you don't have an 800MHz antenna, pick one up from Radio Shack. They run around $15-20, and will greatly improve east site reception over a stock antenna, and it might be all you need to get the west site.
Hope this helps.