This is not something I provide, but I just love the idea, and have sent many. I can highly recommend this site!
You can find them here: "Mail a Tree"
Mail-A-Tree is a live Colorado Blue Spruce (sent to most states) or Meyer Spruce (sent to warm southern states) tree seedling in a 10" reusable tube which creates a micro-climate in which the seedling can survive for up to 30 days before being planted inside or out (planting instructions included). You have your choice of colored end caps, recycled paper and your choice of many poems which may be personalized or create your own message at no additional cost. Mail-A-Tree seedlings are 100% guaranteed to arrive fresh and healthy! Any Mail-A-Tree that arrives less than satisfactory will be replaced immediately if you notify the company within 48 hours of receipt. Mail-A-Tree's may be sent all year round within the USA only. This beautiful little tree is only $8.95 and that includes shipping!