I've been wanting to play a vampire, the full ECL 8 variant, but the whole “being evil” thing bugs me.
Does one always have to be evil when wanting to play a vampire?
Paizo has made this abundantly clear. Looking at the available alignments of the various Vampire templates:
Moroi (LE, NE, or CE) based on modern 'common' vampires. Most common vampire in the Inner Sea region.
Nosferatu (LE, NE, or CE) based on 'classic' vampires. Notably, Ramoska Arkminos is a Nosferatu looking for a cure to Vampirism. He canonically makes appearances in Carrion Crown and Curse of the Crimson Throne AP's (to my best knowledge).
Jiang-shi (LE, NE, or CE) based on oriental vampires. Most common in Tien.
Vetala (LE, NE, or CE) based on Hindi vampires. Most common in Vudrani,
Urdefhan (NE) a vampire-esque offshoot native to the lowest layer Darklands.
As you can see, all forms of Vampirism force the user to have the 'Any Evil' alignment described in the Vampire template.
The only vampire related creature, Dhampir, are a playable (Featured) race that could be any alignment but:
Alignment and Religion: Most dhampirs succumb to the evil within their blood. They are unnatural creatures, and the foul influence of their undead heritage makes an evil outlook difficult to overcome. Those who struggle against their wicked natures rarely progress beyond a neutral outlook.
You can always ask your GM to homerule that this isn't true in their version of the game, but that opens up a lot of debate about 'traditionally' Evil things. Possible arguments for a non-evil bloodsucker include but are not limited to:
The Helm of Opposite Alignment is a Cursed Magic Item that can be created from a Hat of Disguise (or other items) for as little as 450 gp (50% of 900 gp), and will shift your alignment to the opposite of whatever it is originally.
No matter what your original alignment was, if you are a creature under the vampire template, your alignment was shifted to evil, and once you wear the helm, it will become good. There are unwanted side effects of changing your law-chaos axis alignment too.
While not a full-blown vampire (yet), the vampirism corruption from Horror Adventures will slowly turn a character into a vampire. Normally you can gain this corruption by being drained of your blood six or more times in a month, but other methods could exist at GM Fiat.
The way the corruption system works, your corruption progresses under certain actions, which normally allow a save before it can happen. But after 3 failures, your character is so corrupted that she becomes an NPC under GM control.
To avoid the Vampirism corruption from advancing, you must drink blood weekly or make a Will check, failure means your corruption progresses, while success means you starve off the thirst, but the next check's DC increases by 2.
But at Corruption Stage 1, your alignment has shifted once towards evil, meaning that a good character will now become a neutral character. At the 2nd stage, it will shift once again towards evil. Finally, at the 3rd stage, you become an NPC (yes, its harsh and can happen quickly).
But while you are at the 1st stage, you can still live the life of an adventurer and you won't even be considered an undead creature yet. And while still under control of your character, you gain Manifestation Powers every few character levels. Normally every other level you gain under the corruption.
Those powers range from vampiric fangs, to summoning bats, to being able to charm a creature who you succeeded at a diplomacy or bluff check.