Asterisk Callback Script driven by Database

We have a SIP/H232 Gateway where we want to perform callback calls. What we need is an Application and/or system that reads an SQL (pref MS SQL) Database for callback tasks(by a Script?). The Application takes care to initiate a callback calling the two parties (a caller and a target) handling it "as usual" (e.g. a voice that says the connection is in process). The success/unsuccess of the callback connection and the time of the conversation should be written back into the Database. We need also help to install an appropiate asterisk version (e.g. AsteriskNow) bacause we are not skilled in linux installations and prefer to have a black box that performs only the callbacks.