How was the sheet music distributed? Did he have a "record deal"? How did he go from being an unknown with talent to having his music widely distributed?
Also, did he get acclaim, groupies, money, etc? Did he tour to support his music? Would he have been easily recognized as a popular musician when his music was at its peak popularity?
19 days isn't too late to answer, is it? :)
Thanks for the great question...and it has a lot to do with the founding of the giant sheet music presses in America. One thing that is actually very hard to fathom is how popular sheet music became in America. It was very popular (think like owning a CD or mp3 album today). One of the most popular pieces of sheet music "After the Ball" sold one million copies in 1893 and eventually sold 10 million copies in total. (To put it in perspective, the population in America was 63 million in 1890 and 76 million in 1900...so you're talking about almost 14% of the population owning this piece of sheet music...)
Sheet music was already immensely popular with the rise of parlor songs in the middle of the 19th century. Stephen Foster is probably the best known of the bunch and he's actually responsible for a lot of the American "folksong" (even though that's a gross mischaracterization of his songs) such as De Camptown Races, Oh Susannah, My Old Kentucky Home...(etc).
As instrument ownership rose, the sheet music industry boomed. Joplin's success rises from a couple of factors. First--the sheet music industry. Second, the incredible fascination of wihte Americans obsession with black culture. Blackface minstrelsy grew in popularity from the 50s and continued well into the beginning of the 20th century. Ragtime music rose as a variant of cakewalk music...and simply put, Joplin was the best composer at ragtime.
Joplin got his start playing in clubs where he eventually formed the relationship with the John Stark who ended up publishing a significant chunk of Joplin's works. Typically sheet music publishers would just purchase a new piece for a set price (as cited in Joplin's entry in the Grove Dictionary Online, this price was usually $25 or less). However, Joplin was able to negotiate the terms of his publishing of the Maple Leaf Rag to net him 1 cent for every copy sold. Although it was a little slow to take off, he ended up selling 500,000 copies by 1909.
The sheet music culture (as referenced a bit above) is best characterized by Tin Pan Alley, which was a street in New York with a lot of sheet music publishers where composers who churn out dozens of new songs a day. (They only get paid for the initial creation). This is how George Gershwin and Irving Berlin got their start (and eventually their fame). In this regard, Jopin was a bit nontraditional.
Did Joplin have acclaim? Absolutely. His success as a ragtime composer allowed him to take (mostly unsuccessful) ventures in ballet and opera--famously demonstrated by his failure of Treemonisha. Did Joplin have groupies or money--this is a bit harder to answer, but it's likely no. Joplin had a comfortable living, but he actually didn't compose that many rags (all of them can be performed in a bit more than an hour without repeats taken). But without a doubt, Joplin was the face of ragtime music. As ragtime faded with the rise (and new white obsession) of jazz--he was mostly forgotten until subsequent revivals of ragtime in popular culture.
For more on Joplin, I would recommend Edward A. Berlin's King of Ragtime: Scott Joplin and his Era.
Hi, just a suggestion that this question would be worth x-posting to /r/jazz also: you may find more jazz history buffs over there