Most HTML generators have serious flaws. Dreamweaver is the only one that I hear consistently good comments about. Sites that look amateurish damage your credibility and, probably, sales. Clean, professional layouts can be done by amateurs, if they look at professional sites for ideas. Templates available online or in software packages can help.
Amateurs can set up stores using online resources.
There are free options. What to do You really could produce a nice-looking web site yourself, even one that people would buy things from. If you are on a budget so tight that this idea appeals to you, at least promise me that you ll spend a month or more studying HTML and talking to people who have good web sites. Then have a number of web-savvy people critique your site before you decide it s ready to go online. Don t buy any web software until you ve done this.