Hi there,
The Horsehead nebula is one of the targets in the December & January Obs. Challenge. You might want to have a read of the Challenge description, and have a look into the link it has to the IIS thread on the topic of the "Horsey":
http://www.iceinspace.com.au/forum/s...ad.php?t=68833
In a nut shell, if you want to see the Horsehead, YOU NEED a really, really dark sky, and know where to look. It is one, if not THE hardest object to view through amateur scopes. Certain filters may help, and the link contains details on these.
I haven't seen it to date. One of my many tasks this Summer season.
It has reputedly been seen in a 6" scope. Most people I've read quote a 10" is the smallest apeture. Have a go and let us know.
Another helpful tip, if you can't see the Flame Nebula, which is the flame like looking nebula right next to the emission nebula the Horsehead juts into, you have no chance at seeing the Horsey. A very helpful indicator.