Hi....I kinda found some info for you but I will tell you under one condition.....you have to be my friend afterwards lol. Just kidding you don't have to. Well I found you a site where you could submit some of you manga and you could be picked up. They have guide lines for how big they want their mange and I'm kinda sure these are the guide lines for all mangas.
3. All entrants should be aware that winning submissions may be published in an anthology whose page size will be 5” x 7-7/16“. Submissions must be photocopies sent on 8-1/2” x 11” paper and proportionately scalable to a 5” x 7-7/16” format. Please refer to our Mechanical Specification Guidelines for further help.
Here is the site link so that maybe if you wanted you could submit your stuff and maybe become famous one day.
TOKYOPOP :: Rising_Stars_of_Manga's :: Gopro :: Submission Deta
Good Luck! Remember me if you make it big lol
P.P.S. Click that !Thanks! Icon for me to if I helped you I really would like to be thanked lol THANKS