where to get sports data feeds?

i am about to begin putting together a site that would require me to have access to sports scores (specifically NFL football). it would be nice to have up to the minute scores for games in progress too.

i have tired looking around at nfl.com, espn.com and so on but none of these seems to have feeds for scores, just headlines.

and of course the budget for this project is fairly tight so i cant really pay a fortune for the feeds. can anyone point em in the right direction?