Particularly helpful to me, and very readable, is C.S. Lewis' work, in particular Mere Christianity, where he proves, in an informal manner, that there must be a God, and that that God is triune, etc. etc.. These are mainly simple philosophical arguments which only prove the basics and make the Bible acceptable; but as soon as you have arrived at that station, you can make use of a theologian for proving the particularly Reformed dogmas.

As for theologians, the deader, the better, but I assume you know have heard of the great Reformers. [hint]Calvin[/hint]

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Co
Netherlands Reformed Congegration of Kampen
Kampen, The Netherlands

Let the righteous smite me, it shall be a kindness, and let him reprove me, it shall be an excellent oil, which shall not break my head: for yet my prayer also shall be in their calamities. Psalm 141:5