Normally, the only items that can be displayed in the Links toolbar are links to web sites.
For me, I have so many it stretches across the entire screen and adding more doesn't work too well.
But there is a way you can create folders for different categories of sites on the toolbar.
Then you can put many pages into each one.
Also, pages with long names don't take up all that extra room.
1. With Internet Explorer running press Ctrl-B
2. Scroll down to the Links folder
3. Click the Create Folder button
4. Give it whatever name you want for a particular category
5. You can drag any current pages into the appropriate directories at this time as well