I have a Google sitemap with 500 URL's on my site and I wanted to do a new one because I have added quite a bit of new stuff recently (and not sure the person who did the first one did it correctly) and I now have ~2500 URL's. Do I need to delete the first one or can they both be on there? The first one has almost 400 pages indexed and I didnt want to delete it if that would start me back at 0 indexed pages.

Thank you,
Michele

Does anyone know about this? Am i posting this in the wrong place? Any answers at all would be appreciated! Thank you!

I don't know the answer to your question for definite certain, but if you have a sitemap that is already recognized by Google I'd keep it where it is. If the new sitemap you are creating with new products also has all of the same old products you can just replace it with the new one. This should only expand what Google knows about your site, and not drop your results for your current pages. However, everything I've read indicates that you can also just have multiple sitemaps referenced in your Google account. So either way will work.

Thank you, i was leaning toward keeping them both but was afraid of all the duplicate content stuff I hear. I dont know how to check if the URL's in the first sitemap are also in the second or how to remove the duplicated URL's so I wanted to make sure that I wouldnt get penalized for duplicate content in both sitemaps. Thanks for your help ArcoJedi!