After my difficulties with booking airline flights via airline web sites for Jetstar and Virgin Blue in the end I gave up using the airlines web sites and use and using the WebJet airline booking website. Now I have started booking accommodation online for the same short trip around Tasmania.
After a pleasant stay at the Newcastle Beach Youth Hostel I thought I would try Tasmanian hostels in the system. YHA have a very good online booking system. This worked well for the central Hobart based Montgomery's. One catch with the system is that YHA members get a discount when they book a room, even if it is a shared room with non-members. But you have to separately account for the members and non-members on the booking web page.
One point of confusion is the smaller hostels, such as Strahan Backpackers YHA. There does not seem to be any way to book this via the web site. The hostel has a "Rapid Room Number" (0245) which is supposed to be used to identify the hostels to the system. But this number doesn't seem to be listed in the system.
There are no YHAs in Launceston. The Arthouse in Launceston taks a minimalist approach to booking, having an e-mail address to send a query. What they do have on their web site which is useful are google maps to places, such as the city Transit Centre. These links are more useful than the maps usually found on hotel web sites. You are able to customise the map, for example, to see how long it will take to walk, rather than drive.