White Beginner deck

If you had a deck description of what you wanted your deck to do, I could give you more targeted advice. Since I see a somewhat consistent theme of lifegain I will go with that, and I will keep budget in mind.

Soul Sisters. Soul Warden is a good card, and she has a sister named Soul Attendant or something very similar to that. They both do the same thing. Neat, huh? Run four of each and you're off to a good start.

Ajani's Pridemate. He gets bigger everytime you gain life and if you have two sisters out, he will trigger for each of them. That is to say, anytime a source you control causes you to gain life he will get a +1/+1 counter for each source.

Now, those three cards can be a real solid start to a good deck that anybody getting into magic should be able to afford and abtain quite easily. White has lots of cards that produce tokens (for the soul sisters) and gain life (for the pridemate)

Token cards: gather the townsfolk, raise the alarm, triplicate spirits, increasing devotion, blade splicee, captain of the watch

Life gaining: cathedral sanctifier, lone missionary, traveling missionaries, riot control, congregate, true conviction

And one of the best cards for this deck to protect your beloved army is brave the elements. Its fantastic. It gives all your white creaturws protection from the color of your choice until end of turn.

I hope this gave you some ideas and inspiration. Most of these cards are pretty cheap and you should be able to find and trade for them pretty easily.

Good luck!