That's what I do...I make a dummy contact, then put the info in the "Notes" field of the contact. I can tell you, though, that Outlook 2003 running on Windows XP *does* have a limit to the amount of text that it will store in the notes field, and it is much, much less than two pages of text.
I run Outlook 2003 and I can say without question that I have notes fields within contacts that are much
larger than 2 pages. Same thing on the two other machines I have running Outlook 2003.
I just added a test contact with 84,971 characters in its note (measured it in Word). No matter how you define a "page" it can't be more than 42,000 characters! I basically used copy-and-paste within a contact (in Outlook) to make a large note. I picked a contact that already had a fairly large note (18,274 characters) and copied its note, repeatedly, into a new contact. I don't know what the limit is either, but I do know that that wasn't it (it could still hold more).
Plus, the entire note propagated to my iPhone on the next sync. You can't see the whole note (if it's very large) when just just viewing the contact on the iPhone, but if you go into edit mode on the note it is there. The test account's note (with 84,971 characters) took a little time to display in edit mode, but every single character was there (added "This is the end!" while in Outlook so that I could easily tell it wasn't truncated).
I think that if you can't add a large note in Outlook, that it is something to do with your install. Perhaps you added some sort of other syncing solution, prior to the iPhone, for a device with limited note size, and it made sure that Outlook would follow it. Regardless it is not normal in my experience. I just RDP'd into 5 different PCs, all running Outlook 2003 and I created very large contact notes in all of them (same thing with one machine that had Outlook 2002 instead).