Having started a previous thread on this subject I recently bought the Sony ECM-MS907 for £89. I have already used it at a couple of sessions and I am very impressed by the results. Before I bought this I used a cheap mic from the PC (okay but by no means great) and a Vivanco stereo tie pin which cost £30 (very unimpressive).
As for the long play v standard play argument I endorse everything Bernard has already said. If it's just to learn some new tunes mono and therefore long play is fine but if you want to record something worth listening to later go for 74 mins and stereo.