If it is a Tamron "Adaptall" lens it is very easily adapted. You can find EOS mounts for those online. Adaptall system lenses were specifically designed to allow interchangeble mounts, making them usable with most SLR camera systems, simply by changing the bayonet mount.
The mounts are still being produced, though not by Tamron. I bought one from China via eBay for $40 including shipping, to allow me to use a good old manual focus Tamron SP 90mm macro lens. (The one I got is "chipped" so that Focus Confirmation still works... there are cheaper "un-chipped" versions, too... But Focus Confirmation can be very helpful... today's cameras aren't designed to be very manual focus friendly!)
Here's photo of the 90mm macro lens with the EF/EOS mount installed and a Nikon mount alongside. I also have Adaptall mounts for vintage Canon FD, Olympus and Konica camera systems, so can use this lens on any of those.
To help you figure out if yours is also one of the Adaptall lenses... Notice the little turqoise dot on the lens, near the base? That's a registration mark for the mount itself, which bayonets onto the rear of the lens and is something you might look for to determine if yours is an Adaptall lens too. Another identifier for an Adaptall lens is a little chromed button on the side, that's a release for the mount bayonet. Pressing it and twisting the mount, it should come off the rear of the lens.
Here's the 90mm lens and mount on one of my Canon DSLRs...
And here are a couple shots taken with that lens on one of my Canons...
Not bad for a $20 second-hand lens with a $40 Chinese adapter! It's a bit slow to work with, since it's both manual focus and manual aperture control. But that's going to be true with all adapted vintage lenses.
Tamron made a number of excellent, premium quality, SP lenses that used the Adaptall mount system, including: 17mm, 24mm, the 90mm macro shown above, 80-200mm, 180/2.5, 300/2.8, 400/4, 1.4X and 2X teleconverters, plus 350/5.6 and 500/8 "mirror" lenses. I'm probably forgetting a few others.
If, on the other hand, yours is a fixed mount (non-interchangeable) Tamron lens, unfortunately it might not be worthwhile to adapt. There are FD to EF/EOS adapters available. But they are often not worth using because many FD lenses do not adapt well for use on the modern Canon cameras. When Canon went from the FD mount to the modern EF/EOS mount, the lens register or distance from the bayonet flange to the film/sensor plane was changed, so in many cases an adapted FD mount lens will not be able to focus to infinity (how far away it will be able to focus depends upon focal length and other factors)... Unless the FD to EF/EOS adapter has optical elements... which tend to be low quality in the more affordable adapters, often making for pretty lousy image quality.
A lot more info about adapting vintage manual focus lenses can be found here at Bob Atkins' website. There's a separate page there, specifically about the problems and practicality or impracticality of adapting FD mount lenses (whether made by Canon or anyone else) to EF/EOS.
You also might Google for more info about Tamron lenses in general and your lens specifically. I know there is quite a bit of info online about Tamron SP and Adaptall lenses.
Hope this helps!
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Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7D(x2), 50D(x3), some other cameras, various lenses & accessories
FLICKR & PRINTROOM
"Bottom line: Would it be worthwhile to get an adapter for these cameras ..."
IMHO, no! Save your time and money. 
I was hoping to find a use for that dated but like new Tamron 80-210 lens. What I was thinking about was Alan Meyer's comment above - "today's cameras aren't designed to be very manual focus friendly!" That made me think the lens had some life left in manual focus/aperture mode.
Maybe the lens (and my Konicas) will make a good row boat anchor
Bill
