That depends on what you use publisher for. Most people I know who use publisher use it because Word is so lousy for converting Office files to web pages, or others use it because Word simply lacks good templates for publishing certificates, etc. In the latter case, all I can say is that the open source community has great templates, but you may have to look beyond OpenOffice for what you want.
Thanks. I suspected I'd need another program because I do basic desktop publishing, which I've always liked MS Publisher for.