Hey Everyone,
I am new to Audacity I am just getting the feel for it. My question is can someone tell me how long I am able to record one track of audio if I was trying to make an MP3 audio for a web page?
Thank you for taking the time to read this look forward to hearing from you soon.
Richard 
How long do you want it to be? See: Audacity Manual .
You should not make it too long because it will cost your users too much bandwidth.
Gale
I regularly make a two-hour MP3 (at 160), uploaded to DropBox, of my favourite DublinCityFM show for regular interweb attendees who failed to catch the show on any particular Monday night. None of them has complained about bandwith usage.
Indeed I have been a grateful recipient of such an MP3 when my Timer Recording failed one Monday night (the Dublin interweb stream failed, not Audacity).
WC