If you just tried house balls, chances are high that the balls do not fit well, so that you can only hold/handle 9 lbs.. Many new players fall into this pit - the ball does not fit, they take a lighter ball, its holes are even smaller/worse, and it end with an ugly light ball compromise. A good fit is vital for success (and fun!). With a properly drilled ball, I am sure you could add some weight.
Besides, if you wnat to start playing fingertip, JohnP's suggestion is good: check out entry level balls from the big manufacturers, e. g. Power Grooves, Tropical Storms, Tornados and the like. At that low weight and as a beginner, you do not need much more.
Have a pro shop measure your hand and ask for weight assistance, it could be that you can easily handle 11 or 12 lbs. if the ball just fits properly! And then better worry about a good execution of the shot than total hook on the lane. The latter comes automatically with the first, and then you might consider a more sophisticated (and probably even heavier) ball model.
Good luck!
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DizzyFugu - Reporting from Germany
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