I made it using Photoshop. The fonts I used were Brock Script (the "N" and "June 25, 2011") and Book Antiqua ("Chelsea and Brad").
I downloaded Brock Script from www.dafont.com. I can't remember where I downloaded Book Antiqua from, but if you google it you can find a site where you can download it for free.
I used the following tutorial to create my monogram: http://weddingmonograms.blogspot.com/2008/03/letter-behind-monogram-tutorial.html.
The blogger, Brianna Nichole, has some great tutorials. I also love her font bio: http://danandbrianna.com/bio_bio/font%20bio.html.
Random tidbit: Once I got the colors I wanted for the monogram I wrote down the color codes. This has helped me maintain the exact colors for other projects when possible.
Happy monogram making! :)