Marvel Comics made Avengers #1-11 available in digital format.  Details at chrome.marvel.com, all prices are listed at $1.99.

Avengers (1998) #1      Feb 10, 1998     Aug 09, 2011    
Avengers (1998) #2      Mar 10, 1998     Aug 09, 2011    
Avengers (1998) #3      Apr 10, 1998     Aug 09, 2011    
Avengers (1998) #4      May 10, 1998     Aug 09, 2011
Avengers (1998) #5      Jun 10, 1998     Aug 09, 2011    
Avengers (1998) #6      Jul 10, 1998     Aug 09, 2011    
Avengers (1998) #7      Aug 10, 1998     Aug 09, 2011    
Avengers (1998) #8      Sep 10, 1998     Aug 09, 2011    
Avengers (1998) #9      Oct 10, 1998     Aug 09, 2011    
Avengers (1998) #10     Nov 10, 1998     Aug 09, 2011    
Avengers (1998) #11     Dec 10, 1998     Aug 09, 2011    

AVENGERS #2 (Digital) (09 Aug 2011)

AVENGERS #3 (Digital) (09 Aug 2011)

AVENGERS #4 (Digital) (09 Aug 2011)

AVENGERS #5 (Digital) (09 Aug 2011)

AVENGERS #6 (Digital) (09 Aug 2011)

AVENGERS #7 (Digital) (09 Aug 2011)

AVENGERS #8 (Digital) (09 Aug 2011)

AVENGERS #9 (Digital) (09 Aug 2011)

AVENGERS #11 (Digital) (09 Aug 2011)