Source for LED Matrix

not sure about power for led matrix, need help?

I am putting together a 8x16 common anode RGB LED Matrix. I will be controlling the display with a Arduino, and using the +5V supply from the controller as my source. My Plan is to source the 16 rows and sink the 8(24 leads, 2colors only, saving the third for a future project). i'm working with 74HC595's to drive and 74HC595's with ULN2803's to sink to ground.

Do i need to use transistors to amplify the current to each row? and if so can i apply 5volts to the collector and the base to the 74HC595, with the emitter leading to the led row?

there is not enough info. why no post schematic too?
what leds we are talking about? what is the If and Vf?

note, when multiplexing, LEDs are operated continuously, they are pulsed 1/8 of the time for example. this means that they will appear dimmer and way around this is to increase current.
next we need to know what is that current and how many LEDs can be turned on together at any point of time (worst case scenario).
suppose you are using LEDs that work fine with 10-20mA but due low duty cycle you figured you expect 30mA to provide good brightness.
if you are driving those LEDs directly from 74HC595, you have to check the datasheet and see if sourcing 30mA is ok (my copy of data sheet says that +/-35mA per output is ok).
so now you have 16x8 matrix so up to 16 LEDs can be turned on at once. current from all of them need to be sunk through ULN2803. in this case 16x30mA=480mA.
quick check of a datasheet says that absolute maximum for collector current is 500mA so we are at the edge of the spec for this part so ULN is the critical part, not 74HC595.
you may now see value in efficient LEDs which can operate at lower current.
next you would need to calculate series resistor for 16 source outputs from two 74HC595,
if the Vf=2.9V for example when If=30mA and circuit is powered from 5V, then

R= (5-Vf)/If=(5-2.9)/0.030=2.1/0.030=70 Ohm
Nearest common values are 68 and 75 Ohm for example.

if you are adding transistor to get more current out of 74HC595, you are going to exceed rating of ULN2803 so circuit need to be redesigned.