As far as I know, there is not a bus from Tlaquepaque to Chapala.
In my opinion ( and being a veteran bus rider) this is the easiest, least stressful and most efficient way to do it.
Take a cab to the Camionera Central Vieja in GDL. Then get on one of the busses that leave every 20 and every 30 minutes. The Primera Plus is 53 ? pesos, I think. The 2nd class one is a little cheaper, but it stops a lot, and you can never tell when it will get to Chapala.
There is a bus that will go to Ajijic via the libramiento and one that goes to the Chapala station. The route through Chapala is easier and more direct.
You can get to Riberas either way. You can take the one to Chapala, get off, cross the street and take a little bus or sometimes a bigger bus that says Jocotepec, and ask the driver to stop in Riberas. Chapala to Riberas is anywhere from 8-10 pesos, depending on the bus.
Alternately, you can take the bus that goes to Ajijic via the libramiento and get off at the stop closest to Wal Mart. Cross the street to the WalMart stop and wait for a bus that is headed to Chapala. It will take you to Riberas, as well. If you take the bus from WalMart towards Chapala, it might be one that meanders thru San Antonio and is a little slower, and will definitely be more crowded.
Some people will tell you to go to "The Alamo" stop on the other side of the carreterra and catch the bus to Chapala from there. I have done that ONCE, and hope never to have to do that again. It is a madhouse. Noisy, full of fumes and smells, tons of people all trying to catch a different bus at the same time. Even if you manage to get the right Chapala bus, you may have to stand all the way to Chapala.
Just my opinion. Good luck on your trip.