I've just spent the last couple of weeks trying to set up the same kind of project.
You do need a persistence.xml file, and it belongs in META-INF
Here is an example of my spring beans file for persistence:
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<context:property-placeholder location="/WEB-INF/config.properties" />
<tx:annotation-driven />
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<bean id="jpaTemplate" class="org.springframework.orm.jpa.JpaTemplate">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${db.driver}" />
<property name="url" value="${db.url}" />
<property name="username" value="${db.user}" />
<property name="password" value="${db.password}" />
</bean>
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="persistenceUnitName" value="whatisayis" />
<property name="dataSource" ref="dataSource" />
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
<property name="databasePlatform" value="org.hibernate.dialect.MySQL5InnoDBDialect" />
<property name="showSql" value="true" />
<property name="generateDdl" value="true" />
</bean>
</property>
</bean>
<bean id="leDAO" class="com.noisyair.whatisayis.dao.jpa.JpaLearningEntryDAO">
<property name="jpaTemplate" ref="jpaTemplate" />
</bean>
<bean id="sampleDAO" class="com.noisyair.whatisayis.dao.jpa.JpaSampleDAO">
<property name="jpaTemplate" ref="jpaTemplate" />
</bean>
<bean id="tagDAO" class="com.noisyair.whatisayis.dao.jpa.JpaTagDAO">
<property name="jpaTemplate" ref="jpaTemplate" />
</bean>
</beans>
Also, I am using Maven to pull in the spring3 and hibernate dependencies i need.
edit: for a learning resource I highly recommend "Spring Recipes A Problem-Solution Approach" by Gary Mac http://www.apress.com/book/view/9781590599792. This is one of the best technical books I've ever read, and it will surely help you get up and running with Spring/JPA/Hibernate.