How to Access an American PhD Thesis?

You could use ProQuest for free at the British Library.

Obtaining theses in the Reading Rooms: North American theses

ProQuest Dissertations & Theses is available online on the electronic resources terminals in Humanities - Floors 1 and 2.

http://www.bl.uk/reshelp/findhelprestype/theses/hrrtheses/theses.html

In general, one could also just write a polite e-mail to the author of the thesis requesting the file (and making it clear that you need it for your research). Unfortunately, in this particular case I was not able to find the author's e-mail by googling.

As a truly very last resort one could try to contact the thesis advisor (which in this particular case can be found through this link) and very politely ask whether he could either pass your request to his/her former student or even provide you with the file of the thesis.

There are a number of ways of accessing American PhD theses. Many, possibly most, US PhD theses are are archived at ProQuest (cf. this question for more about them). In some cases there may be an embargo period before which the thesis will not be available. Some universities have subscriptions to ProQuest allowing you to download the theses from them for free. If your university does not have a subscription, you can purchase the thesis directly from them.

Most US universities have archival copies of all recent theses in their libraries. If you search the library catalogue (as you did in the question), you may find a link that allows you to download the thesis for free (or a fee). If not, it should provide enough information to allow you to make an inter-library loan (ILL) request.

If for some reason you are unable to buy the thesis from a place like ProQuest and you library cannot arrange for an ILL, you can also ask someone at a university with a less inept/cheap library to download, or make an ILL request, for the thesis. Note, however, that this may not be legally allowed by the licensing agreements. Finally, note that the main site of AC.SE is not the place to make such a request, but you could try in the chatroom.