No... There are no legal downloads of XP save maybe those distributed by Technet and similar academic services. If you can still find a copy of Windows XP for sale, you can buy it, and use it without activating for 30 days. If you haven't activated it, you are entitled to a refund from Microsoft for the purchase price.

Of course given that XP is on life support, and that life support is slowly dwindling away to nothing, not to mention it's next to impossible to find drivers for a lot of modern hardware that works with XP, it's an OS better left forgotten. If you have a major hard on for XP for whatever reason, consider going the other way, and buying a copy of Windows 7 Professional or Ultimate, which has the XP Mode feature. Then if you really want, you can basically live inside the XP VM, rarely, if ever, venturing out into the larger world of Windows 7.