Whether It's For Fun or to Make Some Cash, Collecting Baseball Memorabilia Can be a Great Hobby

Once upon a time baseball was the most popular sport in the country.  It became America's Pastime.  There were great players and great teams that captured the imagination of sports fans from coast to coast.  The rise of the NBA and NFL has decreased the popularity of the sport, but there is still a love affair with baseball, especially with those of us that enjoy collecting baseball memorabilia.
 Baseball Memorabilia - Mickey Mantle Baseball Card
Collector's Conventions
The easiest way to find out about the baseball memorabilia industry is to go to a collector's convention.  Just don't expect to walk away with anything unless you're willing to bust open your wallet.  But don't let that scare you away.  You can still have a great time and see some priceless pieces of baseball memorabilia. 
It is not uncommon for collector's shows to have over 1,000 booths for exhibitors to showcase their collections.  You can find valuable baseball cards, baseball, pictures, and autographs at just about every booth.  While there is usually a big crowd and the pieces are expensive, it is still fun to see all the history of the game of baseball before you.
Baseball Cards
Perhaps the most popular of all baseball memorabilia is the baseball card.  Baseball cards have been around longer than Major League Baseball.  While there is dispute over when the first card was actually produced, all estimates are from the time period just after Civil War.  Probably for just as long, people have hunted for valuable baseball cards. 
When I was a kid a very close family friend passed away.  His widow gave his baseball cards to me.  These cards mostly consisted of Topps cards from 1974 to 1975, and included rookie cards of Robin Yount and George Brett.  I remember impatiently waiting each month for the latest edition of Beckett magazine to see the value of those cards.  While they are no longer worth as much as they were back then, it is still a source of pride to have those cards.
Autographed Baseballs
While autographed baseballs can be purchased, they are more fun to collect when you are the one that is able to score the autograph.  It usually takes some effort to get the autograph but there are ways.  First, you can just go to a game, ball in hand and try to get a player to sign it.  The downside to this is that it is hit-or-miss whether players will be available to sign the ball.  Also, if you want the autograph of a certain player there is no guarantee that he will be available. 
Another way to get a baseball signed is to show up for autograph signing sessions.  Collector's shows are a good way to this, but there is usually a charge for the autograph.  Some teams have fanfests before the season and make their players available for autographs for free.  I would recommend keeping an eye out for free autographs.  They can be had, you just have to be patient.
Foul Balls
The foul ball is the piece of baseball memorabilia that is the Holy Grail for many people.  Foul balls will make people do crazy things.  I have seen grown men knock down kids, and I've seen people drop $8 cups of beer for a ball.  But I can relate.  The two foul balls I have are prized possessions of mine.
Baseball Memorabilia - Josh Hamiton Bobblehead
Bobbleheads have grown in popularity in the last decade or so.  Many teams use bobbleheads as a promotional item.  At baseball memorabilia shows there are always several booths that have an extensive bobblehead collection to show off.
Like baseball cards, bobbleheads are said to have originated in the 19th century, with modern bobbleheads debuting in the 1950s. 
Ah yes, the foam finger.  While not solely baseball memorabilia, buying one of these things is always fun.  They are easy to come by and always put a smile on people's faces.  There are also other versions which need PG-13 ratings.  Use your own discretion when showcasing those!
Collecting baseball memorabilia is a fun exercise that can be rewarding financially.  But more fun is just knowing that you own a piece of baseball history from collection baseball memorabilia.