Depending on your needs, I can write you a custom online database editor in PHP or ASP. You specified Windows based, so if available I would say that ASP would be ideal, but since this sounds like a relatively basic app, either PHP or ASP should be just fine.
Also this bid is a rough estimate. Without knowing what type of database, what data types are in it, and how large the database is, could change it a bit. But since I have no prior work here, I'm more than willing to keep the price low to assuage any worries you may have.
Feel free to send any questions or concerns my way, I almost always find myself in the vicinity of a computer and am able to respond rapidly.
Thanks for consideration,
Eric