My site was running extraordinarily slow over the last week or so. A few days ago I purchased more bandwidth and around the same time it was implemented my site started screaming. I'd like to determine if the change in performance was due to a change on my site's server, somehow related to the additional bandwidth, or it was maybe just network-related. Is there any way to check if the server where my sites resides was changed or if my site was possible moved? Thanks.
The site wasn't moved unless you requested it to be moved. Adding bandwidth doesn't affect site performance, it only increases the overall monthly quota of bandwidth available for your account. It doesn't increase the bandwidth available at any given moment. That is consistent across the entire network. I would suspect that any performance increase you see after ordering bandwidth is coincidental, and as you suggested, the slowing you saw previously was network related rather than server related.