as one of the other answers says there is a lot of good help available by pressing F1.

These two links take you to the official Microsoft web sites that have lots of tutorials & videos.
http://office.microsoft.com/en-us/access/FX100646921033.aspx?CTT=96&Origin=CL100570041033 – 2003
http://office.microsoft.com/en-us/access/FX100646911033.aspx?CTT=96&Origin=CL100570041033 – 2007

There is a developers centre here:
http://msdn.microsoft.com/en-us/office/aa905400.aspx

There are also forums there where you can ask questions and get answers from Microsoft Access experts.
http://msdn.microsoft.com/en-gb/office/aa905410.aspx

Others will offer external sites with good information but as a starting point Microsoft will be the best place to go.
Microsoft are the best people to learn it from are the people who wrote it.

as one of the other answers says there is a lot of good help available by pressing F1.

These two links take you to the official Microsoft web sites that have lots of tutorials & videos.
http://office.microsoft.com/en-us/access/FX100646921033.aspx?CTT=96&Origin=CL100570041033 – 2003
http://office.microsoft.com/en-us/access/FX100646911033.aspx?CTT=96&Origin=CL100570041033 – 2007

There is a developers centre here:
http://msdn.microsoft.com/en-us/office/aa905400.aspx

There are also forums there where you can ask questions and get answers from Microsoft Access experts.
http://msdn.microsoft.com/en-gb/office/aa905410.aspx

Others will offer external sites with good information but as a starting point Microsoft will be the best place to go.
References :
Microsoft