As a Criminal Defense attorney in Berkeley, Charleston, and Dorchester, I use these resources all the time. They are sometimes difficult to find, though, and so I thought I would pass the links on to you.
Jail / Inmate Search
Berkeley County Jail Inmate Search
Dorchester County Inmate Search – (via Vinelink.com)
Charleston County Inmate Search
Public Indexes / Public Records Search
The public indexes allow you to search online for pending cases against an individual. It will tell you basic information about the case, such as the warrant number, charge, attorney, and prosecutor assigned. The public indexes are below.
Dorchester County Public Index
Charleston County Public Index