I agree with Brian S. that you're probably not gonna have much luck just popping onto this list and getting a response to your request.
On the other hand, if you live in a bigger city, you might try going to a show that is apt to have tapers in attendance and then strike up a friendship with them. If you have a particular show in mind that you want recorded, maybe you could offer to buy them a ticket and a couple of beers to show up if they'll record it for you. I think that if you are honest and truly intend to make good on this offer, many tapers would accept. Then after there's some trust built, they might let you borrow their gear outright.
In order to find places where tapers hang out, you should a) familiarize yourself with the venue's in your area that are taper friendly...then go there and look for the stands, or b) check your newspaper for listings of bands coming to your area that are taper friendly and go see those bands and seek out the tapers. To determine bands that are taper friendly, go to
www.archive.org and consult that list of bands that allow taping BTAT.
Don't be shy. Most tapers are pretty happy to help out a newb...especially if you're truly intent on following up on your offer. OTOH, if you're 18, have no money and are looking for free handouts, you should DEFINITELY wait until you're serious. We're a friendly bunch on this list and we like to 'give back', but generally charity is not where we're at.
Hope this helps.