Earlier versions of Word were able to import AppleWorks documents, but I'm
not sure if Word 2004 and Word 2008 can still do that. Another solution
would be to buy MacLink Plus, which does batch-conversions and can translate
your AW documents into a wide variety of different formats:
While there are free scripts out there, this question has a lot of
different variations and issues that you could run into that would take
a lot of time to work around, so it's probably worth just biting the
bullet and paying for MacLinkPlus (that Michel linked), which is a more
extensive program that should already have taken all these issues into
account.