The stuff about not having to camp is a useful one. I've done a mixture of camping/YHA/B&B tours over the years, and each has their own positives and negatives.
Do you have an idea of what sort of touring you want to do? If it's out and out rough tracks off road stuff then you may want to consider a mountain bike. If it's road touring and staying in hotels every night then your road bike will probably be fine.
For specific tourers, especially if you are looking for drop bars, then the Revolution Country Explorer looks good, and it's cheaper Aluminium framed Country Traveller are both well regarded bikes.
The Dawes range has been muddied by all being renamed as some sort of Galaxy, but all of them are decent at different price points.
Otherwise if you want a european style bike then look for trekking hybrids, which are probably a bit cheaper. I'd keep some budget back on those for bar ends or even fitting butterfly bars for the hand positions, but there are a number out there that make very capable tourers.
Look for 36 spoke wheels if possible, and I would probably recommend disc brakes (even though I tour fully loaded up using canti brakes on my horizon) for the extra stopping power, but with your sort of budget you should be able to get a nice bike, whatever your specification you decide you require.