Hello from dfw area. Need help sexing bp

Hi friends, I live in the Mckinney area in North Texas and I was hoping someone with experience in the area would be willing to help me learn to sex my snakes. I have 4 ball pythons, three of which are males from known breeders. I got a normal "Female" ball python pos het albino on Craigslist a few months ago. Super friendly snake that I love but I am doubting its gender. I attempted to pop it but I am afraid of hurting it. I got a whitish sticky substance to come out of the cloaca, which makes me think sperm plug. I will be very sad if it's a boy, but such is life and such are CL buys. Does anyone have a probe kit that could show me how to use it if I purchased probes? The snake in question is over 1100g and I am sure probing would be my best bet. I also plan to breed in the next few years and would like to know how to sex hatchlings. So your help is much appreciated if you have any ideas for me. Thank you!

Is there a vet in the area that anyone has experience with that could sex a snake for me? I have heard of Dr. Hickman in Mckinney. Does a vet usually charge much for sexing?

It's all about the technique and not how hard you pop them.
Ralph Davis teaches the "roll it up like a tube of toothpaste" method which works fantastic and isn't too hard to learn...

http://www.youtube.com/watch?v=BPmIpc_gP9I

The white stuff you speak of is urates(pee), not a plug.

I thought it could be urates too, but it it is clearish white and the consistency of snot. If that makes sense. could this be normal discharge for a female?

Well, thought I would update this. I took "her" in to a local pet store to get probed. As suspected, it is a MALE! Ugg! There goes my breeding plans. It was sold to me a female pos het albino. Turns out it's a male 100% het for "you have been taken on CL". I should know better but I took them for their word. Oh well. I paid $80 for an adult normal male. I am bummed to say the least.

I thought this was a good video, cleared up a lot of questions for me. For future reference. So sorry you got taken by someone :(

http://www.youtube.com/watch?v=9QqW_PhMBEY