I'll respond to part two of this first.
I'm one person. I have taken an average of 18 questions a day, every day since Jan 1, 2000. Not just business days -- every day. That is well over 15,000 questions so far. I'm just one person -- there are LOTS of resources out there. I might suggest that:
a) the USENET newsgroups, freely available from www.google.com, are a great resource. I can be found there, as well as many other extremely knowledgable people -- all willing to try and help you.
b) </code>
http://otn.oracle.com/ <code>has discussion groups where other Oracle developers hang out. Great place to post a question and get an answer (and maybe even answer a question or two yourself)
c) search works really well. A search for excel on this site returned subjects like:
"Automate loading of data from Excel spreadsheets into database"
"Storing & Retrieving Excel Spreadsheet in DB"
"How to import data from more than one (.csv ) [Excel] files into the related tables !"
for example. In your case, I might
1) save the excel data as CSV (comma separated values)
2) use sqlldr to load it (the csv file)