This card's name becomes "Amazoness Queen" while on the field or in the GY. If this card is Normal or Special Summoned: You can add 1 "Amazoness" Spell/Trap from your Deck to your hand. You can only use this effect of "Amazoness Princess" once per turn. When this card declares an attack: You can send 1 other card from your hand or field to the GY; Special Summon 1 "Amazoness" monster from your Deck in Defense Position, except "Amazoness Princess".
You won't be able to activate traps that you get right away, but this is a useful way to get Amazoness Onslaught from your deck. Amazoness Onslaught is a powerful trap that lets you banish your opponent's monster whenever your Amazoness monster attacks them, as well as gaining an additional normal summon during each battle phase. If you already have it in your hand/field, then you can use Amazoness Princess' effect to get spells that you can use right away. Heirloom has a slightly similar effect, and Fighting Spirit helps you get over some high attack monsters.
With Amazoness Princess' third effect, you can special summon any Amazoness monster from your deck. If you already have Onslaught active, Baby Tiger is a very useful defensive card that can be brought back multiple times, which also helps with tribute summoning. Alternatively, you can special summon Amazoness Queen from your deck so you don't have to tribute a monster. This will make all your Amazoness monsters you control cannot be destroyed by battle.
Since Amazoness Princess' effect to add a support spell/trap can be activated whenever it's special summoned, you can use Amazoness Willpower and Powerful Rebirth to special summon from the grave, which will let you re-use her effect again to get another spell/trap using the same monster.
You can use Amazoness Princess' effect to get a Amazoness Fighting Spirit from your deck if you are going against high attack monsters, and Princess' third effect can be used to summon another Amazoness monster. Since all the Amazoness monsters, except for Amazoness Tigers, are Warrior type, you can increase their attack significantly by using The A. Forces and swarming the field. Sogen can some from Joey's skill Fields of the Warriors so you don't have to bring it in the deck.
Here are some of the monsters you can search out and special summon with the effect of Amazoness Princess.