You may not be too bad off. It sounds like you're currently receiving SD only programming from E* and using the 811's OTA tuner for HD locals. That's not a bad compromise and is probably your best bet for HD football programming for now and at minimal cost. As long as you're getting your local network channels in HD, you're getting most of what's available NFL football-wise. Of course you won't get games on ESPN HD and ESPN2 HD, and NFL Network HD does have some interesting programming but no real-time games (yet) and not much in HD. (They will start carrying selected, exclusive games in HD after Thanksgiving.) And there's CFL on WorldsportHD if you're interested in that league.
If you're not currently on a commitment, why not get one of the upgrade packages like the 211 for $49 and get the additional 10-mo. programming discount on an HD package? That way you'll only make a minimal additional investment and you can avail yourself of all the HD programming E* and your local channels offer. I think you could have that for as low as $45 per mo. during the discount period, plus taxes and additional equipment fees (if any). You can keep the 811 for a second HD receiver (add $50?), but as others mentioned, it will only be able to receive the "old" (MPEG-2) HD programming channels which unfortunately does not include ESPN2HD, NFL Net HD and WorldsportHD.
I can sense your frustration (I started with the 811 in Dec. only to see it become obsolete in Feb., but at least I had some of the HD programming) but technology marches on and at some point everything becomes obsolete...!