You're in luck. Summerville is using the Palmetto 800 mhz trunked system, which happens to be a Mixed mode system. Meaning they cater to both analog and digital radios. Summerville happens to be using Analog. So you won't have to spend a lot of money on a digital scanner.
Palmetto 800 Trunking System, Various, Multi-State - Scanner Frequencies
this link is the database you'll be referring to when programming in your stuff. Just get any ole analog trunking scanner, and put in the control channel frequency for Summerville which is in red it's (858.76250) and set the scanner to control-channel mode only. The scanner will do the rest. Then all you need to do is program in the TALKGROUP for each agency channel you wish to listen to. The talkgroup is the DEC number listed below. So to listen to Summerville FD you'd program in 14896, or if you wanted to listen to Summerville PD Dispatch you'd program in 14928, and so on. In trunking, the TALKGROUP is like a channel number for whoever you're listening to. The trunking system randomly assigns a frequency to the talkgroup at any given time. The trunk-tracking scanner is able to follow along with the system. So all you need to worry about is the talkgroup id in the DEC field. Program it how you like and follow Mike's link to how to become a feed provider...
Summerville City (Dorchester County) Talkgroups
DEC HEX Mode Alpha Tag Description Tag
14896 3a3 A Smvl FD Summerville FD Fire-Tac
14816 39e A Smrvl FD FG1 Summerville FD Fireground 1 Fire-Tac
14768 39b A Smrvl FD FG2 Summerville FD Fireground 2 Fire-Tac
15024 3ab A Smrvl FD FG3 Summerville FD Fireground 3 Fire-Tac
15184 3b5 A Smrvl FD FG4 Summerville FD Fireground 4 Fire-Tac
14928 3a5 A Smvl PD Dis Summerville PD Dispatch Law Dispatch
14864 3a1 A Smvl PD Tac Summerville PD Tactical Law Tac
14832 39f A Smvl PD Rec Summerville PD Records Law Talk
14880 3a2 A Smvl PD Narc Summerville PD Narcotics Law Tac
