I don't know what kinds of drivers you are missing, most of the common drivers can be handled by Xp, update Xp SP2 may a little help.
For early Xp version, the major problems are the mainboard chip INF file, VGA driver and sound card.
Check your hardware device in control panel, if there is any "question" icon, record down and go search from internet to get the latest drivers or go directly to the manufacturer web site. But do alert that there is possibilities no Xp OS drivers if the hardwares are old enough.
Anyway, there is no way fpr you to skip the above procedures because Xp is not a superman, it can't do everything for you. Some kinds of headache for newbie...
For two OS, since your existing hardware already fully occupied by WinME, add a new hard disk into your PC, boot up Xp install CD , when it prompts you where to install, select the new hrad disk and go on rest of the steps. After Xp is installed and computer boot up, a config menu will prompt you select which OS you want to start, you can pick WinME or XP either.
Note: If you format the new Xp partition in NTFS format, start WinMe can not see it, therefore, during Xp installation, do not format as NTFS. If your new hard disk is not more than 20G, Xp only allows you format FAT32, and that's OK for both OS to see each other.