Hi!
I am not an accountant or a tax professional.... but this is what I know!
If you live in Kansas and sell/ship to someone outside of Kansas, you do not need to collect sales tax.
However, If you live in Kansas, and sell to someone within Kansas, you need to collect, report, and pay sales tax you have collected. How much you collect depends on where you live (county and city). You will also need to register for a sales tax certificate.
You can get more info here -
http://www.ksrevenue.org/business.htmlGive them a call if you have questions. I called when I moved to KS from OR (a sales tax free state), and they were really helpful.
Once you get your tax rate, you can enter it in your Etsy shop by going to 'your account' on your Etsy page, under 'shipping and payment' is a tab for sales tax. Enter in the fields, and it will automatically calculate tax into the final cost for shoppers in Kansas.
Hope this helps! :)