Need help with append function in vb.net that will work with excel

Hi Codeguru,

Is there an append function in vb.net that will work with excel sheets?

Say for example I read 5 excel files, extract data from them and do some calculation then generate another (say AAA.xls) excel sheet and put them into that sheet. So next time I rerun the program and have different 5 excel files. So I will again extract data and do the calculation and then want to append the results into AAA.xls without overriding the existing data. So I think I need an append function to work with excel. Can anyone tell me how I can do that and if you guys can direct me to a website where I can find more on this topic, I will appreciate it.

Thanks,
raf35