I just finished up the fourth and final part to the Wizard and posted it to my site at XNADevelopment.com. This final installment in the series covers adding the ability to have the Wizard shoot magic fireballs. So creating projectiles and maintaining them it covered in the tutorial.
This has been a fun (but LONG) set of tutorials to write. Let me know what you think of them so I can either continue doing tutorials in this style or adjust them. I'm always happy to hear feedback. Several things I've changed about the tutorials and even about the site layout itself has been from feedback I've received from the community.
Head on over and checkout The Wizard: Part 4 - Making a Sprite Shoot Fireballs and let me know what you think.