dannyjmusic
You can download Reaper and it will do exactly that
yes reaper just does it, change tempo in the transport, hit enter, done, I have done it in the past with quite large differences in tempo, zero artifacts, and no discernible sound quality loss. studio one also will do it like that, although not quite as quick, after you change the tempo in the transport and hit enter it will do a little dance for a few seconds and then you are on your way. with sonar i have done it the way craig anderton pointed you to in another thread, the link to the tips and tricks section he gave you, and it works just fine, although more work required.
whatever way you do it as long as it works and does what you want it's all good