You cannot import excel files directly. But there are two ways to import CSV files.
1) Create a table with a structure 'matching' the data in the file. Now you can 'import' from teh table menu or context Wthis you can import and all sorts of text files with data whetehr comma delimited, semicolon delimited or TAB delimited.
2) use the Migration Tool. Define a DSN with the Microsoft text ODBC driver pointing to a specific folder. Every supported file (type) in that folder will be considered a table by the driver. If you have problems with that please detail the problems!
related FAQ's:
http://webyog.com/faq/28_73_en.html
http://webyog.com/faq/17_88_en.html