Many of us now dont use cassette deck, but if you like me we both do.....
Some anformation and features you may consider before purchaseing,
Auto Reverse, is a good featue this alows you to play both sides of the cassette without ejecting it, most hi-fi separates have this function
Dolby, comes in B - C and HX-PRO These are noise re-duction circuits to reduce background hiss that you get on cassettes Dolby B is the most populat Dolby C is an inhancment of B - HX-PRO is headroom Extension this helps the dynamics of the recording sound even better.
Bias Ajustment - This feature is maily on premium decks this can be ajusted to match slight differnces in the cassettes used
Rec level - Some basic decks may have AVL = Automatic Volume Level this recorded the level automatic to the cassette others will have a manual recording level this is a simple feature to use and can benifit you when recording from a poor souce.
Full Logic vs Manual - Some decks will have manual keys to operate the deck othough this method has been used for many many years they do have a chance of bending and damaging the heads on cheap models, on the other end Full Logic is fully automatic you still have to press a button but the deck does the work and are very reliable in most cases, this is beacuse the deck has to be more exact.
New vs Second hand - Well we are now in 2008 and there is not many new models produced now - i have often purchase second hand and if you can put up with some marks and normally everything works very well and you can sometime buy them for less than £20 quid.
Cassettes - The choice of cassettes is mainly down to you, but using brand tapes is normaly the safe purchase - types of cassettes to use
Ferric - These are standard type offering you good recording of everyday music
Chrome - These offer a higher quality recording for recording off CD's
Metal - These offer even higher quality ideal for studio sound recording
c60 - c90 or c120, well almost all make only reccomend c60 and c90 tapes but many use c120 and in fairness the use of c120 is fine in high quality cassette decks.
All round go for as much as you can aford, going for models like Sony - Technics - Aiwa are all good choices
And remember always have fun