you must have heard wrong
Valerian has MILD GABA effects.
It smells horrible (to each their own though), doesn't taste much better by itself though you can mix it with other herbs like chamomile and lemon balm or lemon grass to ease the taste.
that being said, one would need to ingest a very large quantity of valerian to have the same gaba effects as a small dose of valium.
herbal teas are nice, but, they tend to be more psychological. They will ease your anxiety somewhat. So for someone who has major anxiety issues, this can feel euphoric in the benzo sense, but for most people, just drinking herbal teas will NOT get you "high"
you should be able to buy valerian in tea form at your local herbal/natural food store, in capsule/pill form at most pharmacies like CVS, Walgreens etc. It will be in the sleepy section of pills/supplements near melatonin and the like.