The Collaborative International Dictionary of English v.0.48:

Inexpensive \In`ex*pen"sive\, a.
   Not expensive; cheap.
   [1913 Webster]

WordNet (r) 3.0 (2006):

inexpensive
    adj 1: relatively low in price or charging low prices; "it would
           have been cheap at twice the price"; "inexpensive family
           restaurants" [syn: cheap, inexpensive] [ant:
           expensive]

Moby Thesaurus II by Grady Ward, 1.0:

22 Moby Thesaurus words for "inexpensive":
   budget, cheap, easy, economic, economical, economy, frugal, low,
   low-priced, manageable, moderate, modest, nominal, popular,
   reasonable, sensible, shabby, shoddy, token, unexpensive,
   within means, worth the money