hahahaha I think i answered your other question a moment ago :P Alright. There aren't very many tutorials on this-- actually, there are so few, I can't find any xD But I'll give you some reference material you can try:
https://www.google.com/search?q=movie+roll+film&hl=en&safe=active&rlz=1C1AFAB_enUS471US471&prmd=imvns&source=lnms&tbm=isch&ei=SKqMT_rVDOj50gGSxazuCQ&sa=X&oi=mode_link&ct=mode&cd=2&ved=0CB8Q_AUoAQ&biw=1280&bih=899#hl=en&safe=active&rlz=1C1AFAB_enUS471US471&tbm=isch&sa=1&q=clock+gears+drawing&oq=clock+gears+&aq=0&aqi=g10&aql=&gs_l=img.1.0.0l10.2452l2452l14l3392l1l1l0l0l0l0l62l62l1l1l0.&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&fp=e6453efcd31d9eb&biw=1280&bih=899 <-- search for more references on google images-- those work fine
If you want a step by step instruction, draw a circle. No, seriously. Draw a circle, then make marks on the paper where you want the gear teeth to go. I recommend using a ruler for this, because uneven teeth spaces tend to look... well, uneven. You can do the classic 'flat' teeth, or you can have a little bit more fun and do jagged, pointy, or whetever suits your drawing. When you're done you can focus on the inside. Have an idea in mind and make holes in your circle-- like this gear:
http://www.google.com/imgres?num=10&hl=en&safe=active&rlz=1C1AFAB_enUS471US471&biw=1280&bih=899&tbm=isch&tbnid=cRRbq_1UhmVQjM:&imgrefurl=http://lumberjocks.com/CaptainSkully/blog/15100&docid=Q3uLfP9Z247t0M&imgurl=http://www.wickedcode.com/temp/simplicity/clock04.jpg&w=505&h=503&ei=MKyMT5eoH6rZ0QHd0JS9CQ&zoom=1&iact=rc&dur=825&sig=103549160463441401952&sqi=2&page=1&tbnh=156&tbnw=157&start=0&ndsp=23&ved=1t:429,r:8,s:0,i:85&tx=115&ty=103
You're not subjected you having a CIRCLE as your base, but as a beginner, i think it's 'safer' to practice on simple things first. When you're able, have fun with this:
http://www.google.com/imgres?num=10&hl=en&safe=active&rlz=1C1AFAB_enUS471US471&biw=1280&bih=899&tbm=isch&tbnid=CpbzHfG_G0cScM:&imgrefurl=http://spectrum.ieee.org/geek-life/profiles/engineering-the-10-000year-clock/3&docid=tP-miZ0oiqcE-M&imgurl=http://spectrum.ieee.org/image/1947914&w=811&h=879&ei=MKyMT5eoH6rZ0QHd0JS9CQ&zoom=1&iact=rc&dur=260&sig=103549160463441401952&sqi=2&page=1&tbnh=169&tbnw=156&start=0&ndsp=23&ved=1t:429,r:17,s:0,i:105&tx=116&ty=108
And if you want ideas on steamy clock gear people (literally steamy, i don't mean hot) check out Hollow Fields. It reeks of clockwork and things like that. And, if I weren't a teenager, I would SO totally go for Claude McGinty :P Lucy is a lucky, lucky red-headed ball of heart >.<