Just a quick message having spoken to Thomas, the webmaster, who suggested this forum might be the right place!!
In brief, over the past few years I have worked on a website devoted to accommodation connected to famous figures from history. As it is, I've just added a new section which makes it even easier for visitors to find a place to stay linked to an individual they might be interested in, including Boswell (his entry is here http://www.nightsinthepast.com/historic-figures-b.html)
Anyway, I would be extremely interested to learn of any other places he might have stayed in addition to the couple that I've already listed. All information gratefully received!!