Did Not Receive Maude's message to start Bail Bond missions?
Solution 1:
After the mission "Mr Philips" with Trevor, you should see an orange question mark appear near Sandy Shores - this is the Special Bonds mission where you meet Maude.
About 5 minutes after this she sends you an email with a map of the location of Ralph Ostrowski, the first of the "Bail Bonds" missions.
Now, I did this first mission successfully, and then she sent me another email for the 2nd Bail Bond mission, but it has since disappeared! Same problemo I think. I had to google for Larry Tupper's whereabouts, and sure enough he was there, even without the email.
As long as you've met Maude already, I think you are going to have to google for the whereabouts of Ralph and I'm sure he will be waiting for you there, even though the email has disappeared/or you never received it.
Just in case you are wondering, Ralph is located at:
At the bottom of Davis Quartz Quarry (southeast of Sandy Shores, other side of Senora Freeway)