I acquired a few things, one of them being a webster bandspanner.
Anyone know anything about these?
Whats the best way to mount it?
How do I feed it?
What markings are what bands?   etc...

I suggest you Google or do a search for "Webster Bandspanner Antenna" and there is many pages related to this antenna, of which an ad for a manual.  I use to have one back in the '60s and it worked pretty good on 75m AM.

K6YDW

I did but I didn't find anything really useful, just a bunch of oldtimers saying that had one in 19xx on their xxxxx xxxxxx.

One thing I found said it mounted on a  "3/8" UNF base"  and I have no clue what that is.
My local radio house lists no such item. It could be UHF I guess instead of UNF, but they list UHF base's and 3/8" bases separate.  It's pretty much as clear as mud.

UNF I believe is the 3/8"x24 thread FEMALE mount.  My Bandspanner had a MALE 3/8"x24 thread mount on the bottom of the antenna.  What is your mount??  I had mine mounted on a Super Heavy Duty (From a police car) spring mount.  It's been so long that I dont recall the settings on the antenna either.  You could get a Grid-Dip meter and check it a various locations for resonance I suspect.  I am curious as to if the taps are even any good after so many years also.  Good Luck, 73, de John K6YDW

The mounting end is what you describe 3/8" male.  I only received the antenna, nothing else.
So this will go on something like those spring mounts, the ones I'm thinking of and seen recently are milsurp?
Now that I know what I'm looking for, I can probably find something.  
Thanks for your help.

I got my first HF rig as well.  I can only tx on part of one band(lower part of 10m) on it right now.  Hopefully I'll take the general exam at the end of this month if I get to studying.