Access is actually great. The State of Texas leases several sites where they release trout for the public free of charge. There are several other campgrounds that charge around $10 for day use. If you join the Guadalupe River TU lease access program, you will have access to around 15 locations where GRTU release their trout at.
When in November are you going? Since all the rain a lot of the cold water in the bottom of the lake got released early in the summer the river warmed up and very few trout likely made it through the summer. GRTU has not released their trout yets this year and won't until the river cools down. The State of Texas should post when they will be releasing their trout. If you can, you should to wait till late Nov, GRTU should have released their first batch by then. The avg State of Texas trout is 10" - The avg GRTU trout around 15" with some 20"+ trout usually mixed in.